| Apostroph | apostrophe |
| apokryph | apocryphal |
| Anastrophe | anastrophe |
| Apastron | apastron |
| autotroph | autotroph |
| auxotroph | auxotrophic |
| Apostatin | apostate |
| Apostelin | apostle |
| Apostille | apostille |
| Apostolat | apostolate |
| Apokarp | apocarp |
| apokarp | apocarpous |
| Apokope | apocope |
| Apokryphe | apocrypha |
| Apoptose | apoptosis |
| Apostasie | apostasy |
| Apostat | apostate |
| Apostel | apostle |
| Postdoc- | postdoctoral |
| Posthorn | post horn |